Refrigerant distributer, heat exchanger, and air-conditioning apparatus

ABSTRACT

A refrigerant distributer includes a plurality of plates. The refrigerant distributer is configured to divert, into a plurality of refrigerant flows, refrigerant flowing in from one or a plurality of inlet ports thereof and allow the refrigerant flows to be let out from a plurality of outlet ports thereof spaced from one another in a first direction. The plurality of plates include: an inflow plate having one of the plurality of inlet ports; a communication plate having a communication chamber communicating with the one of the plurality of inlet ports of the inflow plate; and a heat transfer tube insertion plate into which a heat transfer tube communicating with one of the plurality of outlet ports is inserted, the heat transfer tube insertion plate having heat transfer tube insertion space through which a plurality of the heat transfer tubes communicate with the communication chamber.

CROSS REFERENCE TO RELATED APPLICATION

This application is a U.S. national stage application of InternationalPatent Application No. PCT/JP2020/022246 filed on Jun. 5, 2020, thedisclosure of which is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a refrigerant distributer, a heatexchanger, and an air-conditioning apparatus. The refrigerantdistributer is configured to divert, into a plurality of refrigerantflows, refrigerant flowing in and allow the refrigerant flows to be letout.

BACKGROUND

In recent years, to reduce the amount of refrigerant and improve heatexchanger performance, there has been a tendency for heat exchangersusable in an air-conditioning apparatus to include heat transfer tubeshaving a smaller diameter. When the diameter of heat transfer tubes isreduced, it is necessary to inhibit an increase in pressure loss ofrefrigerant that passes through the heat transfer tubes. Thus, thenumber of paths in a heat exchanger, the number of paths being thenumber of branch paths along which refrigerant flows in the heatexchanger, is increased.

To increase the number of paths, heat exchangers usually include amulti-branch refrigerant distributer configured to distribute andsupply, to a plurality of paths, refrigerant flowing in from one inletpassage. For example, Patent Literature 1 discloses a refrigerantdistributer that is disposed to extend in a vertical direction and thatis formed in a header connected to a plurality of heat transfer tubesdisposed side by side in the vertical direction, the heat transfer tubesextending in a horizontal direction. When a heat exchanger functions asan evaporator, this refrigerant distributer includes an inlet pipe intowhich two-phase gas-liquid refrigerant flows, a mixing chamber in whichgas refrigerant and liquid refrigerant forming two-phase gas-liquidrefrigerant flowing in are mixed to form homogenized refrigerant,communication chambers connected to the heat transfer tubes, anddistribution passages through which two-phase gas-liquid refrigerant isdistributed to the communication chambers.

PATENT LITERATURE

Patent Literature 1: Japanese Patent No. 5376010

However, the refrigerant distributer described in Patent Literature 1has a large size, thus resulting in a reduction in the mounting area ofthe heat exchanger. Accordingly, this refrigerant distributer has aproblem of impairing heat exchanger performance.

SUMMARY

The present disclosure is made in view of the problem in the relatedart, and an object of the present disclosure is to provide a refrigerantdistributer, a heat exchanger, and an air-conditioning apparatus, therefrigerant distributer inhibiting an increase in the size and thusinhibiting a reduction in the mounting area of a heat exchanger toenable an improvement in heat exchanger performance.

A refrigerant distributer in an embodiment of the present disclosureincludes a plurality of plates. The refrigerant distributer isconfigured to divert, into a plurality of refrigerant flows, refrigerantflowing in from one or a plurality of inlet ports thereof and allow therefrigerant flows to be let out from a plurality of outlet ports thereofspaced from one another in a first direction. The plurality of platesinclude: an inflow plate having one of the plurality of inlet ports; acommunication plate having a communication chamber communicating withthe one of the plurality of inlet ports of the inflow plate; and a heattransfer tube insertion plate into which a heat transfer tubecommunicating with one of the plurality of outlet ports is inserted, theheat transfer tube insertion plate having heat transfer tube insertionspace through which a plurality of the heat transfer tubes communicatewith the communication chamber.

A heat exchanger in another embodiment of the present disclosureincludes: the refrigerant distributer according to the embodiment of thepresent disclosure; and a plurality of heat transfer tubes connected tothe plurality of respective outlet ports.

An air-conditioning apparatus in still another embodiment of the presentdisclosure includes the heat exchanger according to the other embodimentof the present disclosure.

According to the embodiments of the present disclosure, formation of thecommunication chamber communicating with the heat transfer tubes enablesa reduction in the thickness of the refrigerant distributer, thusinhibiting an increase in the size of the refrigerant distributer andthus inhibiting a reduction in the mounting area of the heat exchangerto enable an improvement in heat exchanger performance.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating an example of theconfiguration of a heat exchanger according to Embodiment 1.

FIG. 2 is an exploded perspective view illustrating an example of theconfiguration of a refrigerant distributer according to Embodiment 1.

FIG. 3 is a schematic diagram for describing the relationship betweenpassages when the refrigerant distributer in FIG. 2 is viewed fromabove.

FIG. 4 is a schematic diagram illustrating an example of the positionalrelationship between the passages when the refrigerant distributer inFIG. 2 is viewed from the front.

FIG. 5 is a schematic diagram illustrating an example of theconfiguration of an air-conditioning apparatus to which the heatexchanger according to Embodiment 1 is applied.

FIG. 6 is an exploded perspective view illustrating an example of theconfiguration of a refrigerant distributer according to Embodiment 2.

FIG. 7 is a schematic diagram for describing the relationship betweenpassages when the refrigerant distributer in FIG. 6 is viewed fromabove.

FIG. 8 is a schematic diagram illustrating an example of the positionalrelationship between the passages when the refrigerant distributer inFIG. 6 is viewed from the front.

FIG. 9 is an exploded perspective view illustrating an example of theconfiguration of a refrigerant distributer according to Embodiment 3.

FIG. 10 is a schematic diagram for describing the relationship betweenpassages when the refrigerant distributer in FIG. 9 is viewed fromabove.

FIG. 11 is a schematic diagram illustrating an example of the positionalrelationship between the passages when the refrigerant distributer inFIG. 9 is viewed from the front.

FIG. 12 is an exploded perspective view illustrating an example of theconfiguration of a refrigerant distributer according to Embodiment 4.

FIG. 13 is an exploded perspective view illustrating an example of theconfiguration of a refrigerant distributer according to Embodiment 5.

FIG. 14 is an exploded perspective view illustrating an example of theconfiguration of a refrigerant distributer according to Embodiment 6.

DETAILED DESCRIPTION Embodiment 1

A refrigerant distributer according to Embodiment 1 will be describedbelow with reference to the drawings, for example. The refrigerantdistributer according to Embodiment 1 configured to distributerefrigerant to flow into a heat exchanger will be described below, butthe configuration is not limited thereto. The refrigerant distributermay be configured to distribute refrigerant to flow into a differentdevice. In addition, in the following description, components having thesame reference signs are the same or corresponding components, and thisapplies to the entire embodiments described below. Furthermore, the sizerelationships of the components in the drawings may differ from those ofactual ones. Furthermore, illustration of detailed structures issimplified or omitted as appropriate. The forms of the components in theentire description are merely examples, and the forms of the componentsare not limited to those in the description.

[Configuration of Heat Exchanger 1]

The configuration of a heat exchanger 1 according to Embodiment 1 willbe described. FIG. 1 is a perspective view illustrating an example ofthe configuration of a heat exchanger according to Embodiment 1. Asillustrated in FIG. 1 , the heat exchanger 1 includes a refrigerantdistributer 2, a gas header 3, a plurality of heat transfer tubes 4, anda plurality of fins 5. The refrigerant distributer 2 has one or aplurality of refrigerant inlet portions 2A, which are inlet ports forrefrigerant, and a plurality of refrigerant outlet portions 2B, whichare outlet ports for refrigerant. The refrigerant outlet portions 2B arearranged in the height direction. The gas header 3 has a plurality ofrefrigerant inlet portions 3A and one refrigerant outlet portion 3B.Refrigerant pipes of a refrigeration cycle apparatus such as anair-conditioning apparatus are connected to the one or the plurality ofrefrigerant inlet portions 2A of the refrigerant distributer 2 and therefrigerant outlet portion 3B of the gas header 3. The heat transfertubes 4 are connected between the refrigerant outlet portions 2B of therefrigerant distributer 2 and the refrigerant inlet portions 3A of thegas header 3.

Each of the heat transfer tubes 4 is a flat tube or a circular tubehaving a plurality of passages. The heat transfer tube 4 is made of, forexample, copper or aluminum. An end portion of each of the heat transfertubes 4 closer to the refrigerant distributer 2 is connected to acorresponding one of the refrigerant outlet portions 2B of therefrigerant distributer 2. The fins 5 are joined to the heat transfertubes 4. Each of the fins 5 is made of, for example, aluminum. FIG. 1illustrates an example in which the number of the heat transfer tubes 4is eight. However, the number of the heat transfer tubes 4 is notlimited thereto and may be any number as long as the number is two ormore.

[Refrigerant Flow in Heat Exchanger 1]

The refrigerant flow in the heat exchanger 1 according to Embodiment 1will be described. For example, when the heat exchanger 1 functions asan evaporator, refrigerant flowing in refrigerant pipes flows into therefrigerant distributer 2 via the one or the plurality of refrigerantinlet portions 2A and is distributed to and flows out into the heattransfer tubes 4 via the refrigerant outlet portions 2B. The distributedrefrigerants in the heat transfer tubes 4 are subjected to heat exchangewith, for example, air supplied by a fan (not illustrated). Therefrigerants flowing in the heat transfer tubes 4 flow into the gasheader 3 via the refrigerant inlet portions 3A and join together. Thejoined refrigerant flows out into a refrigerant pipe via the refrigerantoutlet portion 3B. When the heat exchanger 1 functions as a condenser,refrigerant flows in the direction opposite to this flow direction.

[Configuration of Refrigerant Distributer 2]

The configuration of the refrigerant distributer 2 according toEmbodiment 1 will be described. FIG. 2 is an exploded perspective viewillustrating an example of the configuration of a refrigerantdistributer according to Embodiment 1. FIG. 3 is a schematic diagram fordescribing the relationship between passages when the refrigerantdistributer in FIG. 2 is viewed from above. To make the relationshipbetween the passages formed in plates easy to understand, FIG. 3illustrates the passages with dashed lines. FIG. 4 is a schematicdiagram illustrating an example of the positional relationship betweenthe passages when the refrigerant distributer in FIG. 2 is viewed fromthe front.

As illustrated in FIGS. 2 to 4 , the refrigerant distributer 2 is formedby stacking a plurality of plates 10, which have, for example, arectangular shape. The plates 10 are formed by alternately stackingfirst plates 101, 102, and 103 and second plates 111 and 112. The firstplates 101, 102, and 103 and the second plates 111 and 112 have the sameoutside shape in plan view. The second plates 111 and 112 are partitionplates for partitioning off the first plates 101, 102, and 103. Forexample, a soldering material is applied to both surfaces of each of thesecond plates 111 and 112. The first plates 101, 102, and 103 arestacked via the second plates 111 and 112 and are joined together bysoldering. The plates are each made by, for example, press work orcutting work.

The first plate 101 has one or a plurality of first passages 10A, whichare through holes and which are located at substantially the center ofthe first plate 101 in the short-side direction. A capillary tube or arefrigerant pipe of a refrigeration cycle apparatus is connected to thefirst passage 10A. The first passage 10A corresponds to the refrigerantinlet portion 2A in FIG. 1 . The first plate 101 is an inflow platehaving the one or the plurality of first passages 10A, which are therefrigerant inlet portions 2A serving as inlet ports.

FIG. 2 illustrates an example in which capillary tubes are connected tothe first plate 101. In this case, the first plate 101 has the pluralityof first passages 10A. When a refrigerant pipe is connected to the firstplate 101, the first plate 101 can have the one first passage 10A.

The second plate 111 has one or a plurality of second passages 10B,which are through holes and which are located at substantially thecenter of the second plate 111 in the short-side direction. The secondpassage 10B is formed at a position depending on the position of thecorresponding first passage 10A of the first plate 101 and allows thefirst passage 10A and the corresponding communication chamber 11 of thefirst plate 102, which will be described later, to communicate with oneanother.

The first plate 102 has a plurality of communication chambers 11. Thecommunication chamber 11 is formed to depend on the position of thecorresponding second passage 10B of the second plate 111 and allows thesecond passage 10B and the corresponding third passage 10C of the secondplate 112, which will be described later, to communicate with oneanother. The communication chambers 11 are formed to communicate with aplurality of third passages 10C. In this example, each of thecommunication chambers 11 is formed to communicate with correspondingtwo of the third passages 10C. The first plate 102 is a communicationplate having the communication chambers 11, which serve as communicationpassages communicating with the refrigerant inlet portions 2A serving asinlet ports.

The second plate 112 has the third passages 10C, each of which has thesame shape as the outside shape of the heat transfer tube 4. The thirdpassage 10C holds the end portion of the heat transfer tube 4 insertedthereinto via the corresponding fourth passage 10D of the first plate103, which will be described later.

The first plate 103 has a plurality of fourth passages 10D, each ofwhich is heat transfer tube insertion space having the same shape as theoutside shape of the heat transfer tube 4. The fourth passage 10D isformed to depend on the position of the corresponding third passage 10Cof the second plate 112. The heat transfer tube 4 is inserted into thefourth passage 10D. The heat transfer tubes 4 are soldered to the firstplate 103, and the first plate 103 and the second plate 112 are stacked.Thus, the heat transfer tubes 4 are connected to the respective thirdpassages 10C of the second plate 112. The first plate 103 is a heattransfer tube insertion plate having the fourth passages 10D, each ofwhich is the heat transfer tube insertion space into which the heattransfer tube 4 is inserted.

In this manner, the refrigerant distributer 2 has distribution passages2 a, which are formed by the passages of each of the first plates 101,102, and 103 and the second plates 111 and 112. That is, thedistribution passages 2 a are formed by the first passages 10A, thesecond passages 10B, the third passages 10C, the fourth passages 10D,and the communication chambers 11.

[Refrigerant Flow in Refrigerant Distributer 2]

Next, the refrigerant flow and the distribution passages 2 a in therefrigerant distributer 2 will be described with reference to FIGS. 2 to4 . When the heat exchanger 1 functions as an evaporator, two-phasegas-liquid refrigerant flows into the refrigerant distributer 2 from thefirst passages 10A of the first plate 101. The refrigerant that hasflowed into the refrigerant distributer 2 flows into each of thecommunication chambers 11 of the first plate 102 via the correspondingsecond passage 10B of the second plate 111. The refrigerant that hasflowed into the communication chamber 11 flows into the third passages10C of the second plate 112 that communicate with the communicationchamber 11 and is diverted. The diverted refrigerant flows enter therespective fourth passages 10D of the first plate 103, each of which isthe heat transfer tube insertion space, and are equally distributed tothe heat transfer tubes 4 connected to the respective fourth passages10D.

The example in which two third passages 10C communicate with onecommunication chamber 11 has been described, but the configuration isnot limited thereto. Three or more third passages 10C may communicatewith one communication chamber 11. In this manner, the number ofdistribution paths can be changed by changing the number of the thirdpassages 10C communicating with the communication chamber 11.

[Manner in which Heat Exchanger 1 is Used]

Next, an example of a manner in which the heat exchanger 1 according toEmbodiment 1 is used will be described. An example in which the heatexchanger 1 is used in an air-conditioning apparatus 80 will bedescribed below, but the configuration is not limited thereto. Forexample, the heat exchanger 1 may be used in a different refrigerationcycle apparatus including a refrigerant cycle circuit. In addition, anexample in which the air-conditioning apparatus 80 is configured toswitch between a cooling operation and a heating operation will bedescribed, but the configuration is not limited thereto. Theair-conditioning apparatus 80 may be configured to perform only one ofthe cooling operation and the heating operation.

FIG. 5 is a schematic diagram illustrating an example of theconfiguration of the air-conditioning apparatus 80 to which the heatexchanger 1 according to Embodiment 1 is applied. In FIG. 5 , arefrigerant flow in the cooling operation is represented by dashedarrows, and a refrigerant flow in the heating operation is representedby solid arrows. As illustrated in FIG. 5 , the air-conditioningapparatus 80 includes a compressor 81, a four-way valve 82, an outdoorheat exchanger 83, an expansion valve 84, an indoor heat exchanger 85,an outdoor fan 86, and an indoor fan 87. A refrigerant cycle circuit isformed by connecting, by refrigerant pipes, the compressor 81, thefour-way valve 82, the outdoor heat exchanger 83, the expansion valve84, and the indoor heat exchanger 85.

The refrigerant flow in the cooling operation will be described.High-pressure, high-temperature gas refrigerant discharged from thecompressor 81 flows into the outdoor heat exchanger 83 via the four-wayvalve 82 and is condensed into high-pressure liquid refrigerant by beingsubjected to heat exchange with air supplied by the outdoor fan 86. Thehigh-pressure liquid refrigerant flows out from the outdoor heatexchanger 83 and becomes low-pressure two-phase gas-liquid refrigerantby passing through the expansion valve 84. The low-pressure two-phasegas-liquid refrigerant flows into the indoor heat exchanger 85 and isevaporated, to cool an indoor space, into low-pressure gas refrigerantby being subjected to heat exchange with air supplied by the indoor fan87. The low-pressure gas refrigerant flows out from the indoor heatexchanger 85 and is suctioned into the compressor 81 via the four-wayvalve 82.

The refrigerant flow in the heating operation will be described.High-pressure, high-temperature gas refrigerant discharged from thecompressor 81 flows into the indoor heat exchanger 85 via the four-wayvalve 82 and is condensed, to heat an indoor space, into high-pressureliquid refrigerant by being subjected to heat exchange with air suppliedby the indoor fan 87. The high-pressure liquid refrigerant flows outfrom the indoor heat exchanger 85 and becomes low-pressure two-phasegas-liquid refrigerant by passing through the expansion valve 84. Thelow-pressure two-phase gas-liquid refrigerant flows into the outdoorheat exchanger 83 and is evaporated into low-pressure gas refrigerant bybeing subjected to heat exchange with air supplied by the outdoor fan86. The low-pressure gas refrigerant flows out from the outdoor heatexchanger 83 and is suctioned into the compressor 81 via the four-wayvalve 82.

In Embodiment 1, the heat exchanger 1 is used as at least one of theoutdoor heat exchanger 83 and the indoor heat exchanger 85. When theheat exchanger 1 functions as an evaporator, the heat exchanger 1 isconnected such that refrigerant flows in from the refrigerantdistributer 2. That is, when the heat exchanger 1 functions as anevaporator, two-phase gas-liquid refrigerant flows into the refrigerantdistributer 2 from a refrigerant pipe and is diverted to flow into eachof the heat transfer tubes 4 of the heat exchanger 1. In addition, whenthe heat exchanger 1 functions as a condenser, liquid refrigerants flowinto the refrigerant distributer 2 from the respective heat transfertubes 4 and join together to flow out into a refrigerant pipe.

As described above, the refrigerant distributer 2 according toEmbodiment 1 includes the first plate 101, which has the first passages10A, the first plate 102, which has the communication chambers 11communicating with the respective first passages 10A, and the firstplate 103, which has the fourth passages 10C, through which a pluralityof the heat transfer tubes 4 communicate with each of the communicationchambers 11. In this manner, formation of the communication chamber 11communicating with the heat transfer tubes 4 enables a reduction in thethickness of the refrigerant distributer 2 compared with a case in whichthe refrigerant distributer has a cylindrical shape. Accordingly, it ispossible to reduce the size of the refrigerant distributer 2. Inaddition, a reduction in the size of the refrigerant distributer 2 in anair-conditioning apparatus including a casing having a consistent sizeresults in an increase in the mounting area of the heat exchanger 1.Thus, it is possible to improve the heat exchanger performance.

Embodiment 2

Next, Embodiment 2 will be described. The refrigerant distributer 2according to Embodiment 2 differs from that in Embodiment 1 in thepositions where the first passages 10A of the first plate 101 aredisposed and the positions where the second passages 10B of the secondplate 111 are disposed. In the following description, parts common toEmbodiment 1 and Embodiment 2 have the same reference signs, anddetailed descriptions thereof are omitted.

[Configuration of Refrigerant Distributer 2]

The configuration of the refrigerant distributer 2 according toEmbodiment 2 will be described. FIG. 6 is an exploded perspective viewillustrating an example of the configuration of a refrigerantdistributer according to Embodiment 2. FIG. 7 is a schematic diagram fordescribing the relationship between passages when the refrigerantdistributer in FIG. 6 is viewed from above. To make the relationshipbetween the passages formed in the plates easy to understand, FIG. 7illustrates the passages with dashed lines. FIG. 8 is a schematicdiagram illustrating an example of the positional relationship betweenthe passages when the refrigerant distributer in FIG. 6 is viewed fromthe front.

As illustrated in FIGS. 6 to 8 , the refrigerant distributer 2 is formedby stacking a plurality of plates 20, which have, for example, arectangular shape. The plates 20 are formed by alternately stacking thefirst plates 101, 102, and 103 and the second plates 111 and 112. Thefirst plates 102 and 103 and the second plate 112 are similar to thosein Embodiment 1.

The refrigerant distributer 2 has the distribution passages 2 a, whichare formed by the passages of each of the first plates 101, 102, and 103and the second plates 111 and 112. That is, similarly to Embodiment 1,the distribution passages 2 a are formed by the first passages 10A, thesecond passages 10B, the third passages 10C, the fourth passages 10D,and the communication chambers 11.

The first plate 101 has the one or the plurality of first passages 10A,to which capillary tubes or a refrigerant pipe of a refrigeration cycleapparatus is connected. FIG. 6 illustrates an example in which capillarytubes are connected to the first plate 101. The second plate 111 has theone or the plurality of second passages 10B, each of which is located ata position depending on the position of the corresponding first passage10A of the first plate 101.

Here, when a fluid such as air mainly flows in one direction toward theheat exchanger 1, a part of the heat exchanger 1 located upstream of thefluid flow has a heat transfer performance higher than that of a part ofthe heat exchanger 1 located downstream of the fluid flow. For thisreason, in Embodiment 2, the first passages 10A of the first plate 101and the second passages 10B of the second plate 111 are disposed suchthat a larger amount of refrigerant flows in the part located upstreamof the fluid flow having a high heat transfer performance.

The first passages 10A and the second passages 10B are unevenly providedto be upstream of the fluid flow relative to the central position of theplates 20 in the short-side direction. As a result, when the heatexchanger 1 including this refrigerant distributer 2 functions as anevaporator into which two-phase gas-liquid refrigerant flows, a largeamount of two-phase gas-liquid refrigerant flows in the part locatedupstream of the fluid flow in which the amount of heat exchange islarger than that in the part located downstream of the fluid flow, thusimproving the heat transfer performance of the part of the heatexchanger 1 located upstream of the fluid flow. Accordingly, it ispossible to improve the heat exchanger performance.

As described above, in the refrigerant distributer 2 according toEmbodiment 2, the first passages 10A are formed in the first plate 101such that the first passages 10A are located upstream of the fluid flowoutside the heat transfer tubes 4. As a result, a larger amount ofrefrigerant flows in the part located upstream of the fluid, thusimproving the heat transfer performance of the part located upstreamthereof in which the amount of heat exchange is large. Accordingly, itis possible to improve the heat exchanger performance.

Embodiment 3

Next, Embodiment 3 will be described. The refrigerant distributer 2according to Embodiment 3 differs from that in each of Embodiments 1 and2 in the shape of the communication chamber 11 of the first plate 102.In the following description, parts common to Embodiment 3 andEmbodiment 1 or 2 have the same reference signs, and detaileddescriptions thereof are omitted.

[Configuration of Refrigerant Distributer 2]

The configuration of the refrigerant distributer 2 according toEmbodiment 3 will be described. FIG. 9 is an exploded perspective viewillustrating an example of the configuration of a refrigerantdistributer according to Embodiment 3. FIG. 10 is a schematic diagramfor describing the relationship between passages when the refrigerantdistributer in FIG. 9 is viewed from above. To make the relationshipbetween the passages formed in the plates easy to understand, FIG. 10illustrates the passages with dashed lines. FIG. 11 is a schematicdiagram illustrating an example of the positional relationship betweenthe passages when the refrigerant distributer in FIG. 9 is viewed fromthe front.

As illustrated in FIGS. 9 to 11 , the refrigerant distributer 2 isformed by stacking a plurality of plates 30, which have, for example, arectangular shape. The plates 30 are formed by alternately stacking thefirst plates 101, 102, and 103 and the second plates 111 and 112. Thefirst plates 101 and 103 and the second plates 111 and 112 are similarto those in Embodiment 1.

The refrigerant distributer 2 has the distribution passages 2 a, whichare formed by the passages of each of the first plates 101, 102, and 103and the second plates 111 and 112. That is, similarly to Embodiments 1and 2, the distribution passages 2 a are formed by the first passages10A, the second passages 10B, the third passages 10C, the fourthpassages 10D, and the communication chambers 11.

The first plate 102 has the plurality of communication chambers 11, eachof which is formed to depend on the position of the corresponding secondpassage 10B of the second plate 111. In Embodiment 3, the communicationchamber 11 has a descent inhibiting portion 11 a.

As illustrated in FIG. 10 , the descent inhibiting portion 11 a isprovided such that the descent inhibiting portion 11 a is unevenlylocated to be downstream of a fluid flow. As illustrated in FIG. 11 ,the descent inhibiting portion 11 a is provided to be located lower thanthe position of the corresponding second passage 10B.

In the communication chamber 11, a passage flow resistance applieddownward in the direction of gravity against refrigerant flowing in isusually large. Provision of the descent inhibiting portion 11 a lowerthan the position where refrigerant flows in causes the flow resistancein a lower part of the communication chamber 11 to be larger than thatin an upper part of the communication chamber 11. Accordingly, liquidrefrigerant forming two-phase gas-liquid refrigerant is inhibited frombeing unevenly distributed to flow in the lower part due to gravity. Asa result, the liquid refrigerant flows evenly in the communicationchamber 11. Thus, it is possible to evenly distribute the liquidrefrigerant to the heat transfer tubes 4 communicating with thecommunication chamber 11 when the liquid refrigerant flows out from thecommunication chamber 11 and to improve the performance of the heatexchanger 1.

In addition, the descent inhibiting portion 11 a is provided such thatthe descent inhibiting portion 11 a is unevenly located to be downstreamof the fluid flow. This causes two-phase gas-liquid refrigerant flowingin from the corresponding second passage 10B of the second plate 111 toflow in the part located upstream of the fluid flow more than in thepart located downstream of the fluid flow, thus improving the heattransfer performance of the part of the heat exchanger 1 locatedupstream of the fluid flow. Accordingly, it is possible to improve theheat exchanger performance.

As described above, in the refrigerant distributer 2 according toEmbodiment 3, the communication chamber 11 has the descent inhibitingportion 11 a, which is located lower than the top of the correspondingfirst passage 10A. This inhibits liquid refrigerant forming two-phasegas-liquid refrigerant flowing into the communication chamber 11 frombeing unevenly distributed to flow in the lower part due to gravity.Thus, the liquid refrigerant is distributed evenly to the heat transfertubes 4. Accordingly, it is possible to improve the heat exchangerperformance.

In the refrigerant distributer 2, the descent inhibiting portion 11 a isformed to be located downstream of the fluid flow. As a result, a largeramount of refrigerant flows in the part located upstream of the fluid,thus improving the heat transfer performance of the part locatedupstream thereof in which the amount of heat exchange is large.Accordingly, it is possible to improve the heat exchanger performance.

Embodiment 4

Next, Embodiment 4 will be described. Embodiment 4 differs fromEmbodiments 1 to 3 in provision of a plate having branch passages inwhich refrigerant is diverted into a plurality of refrigerant flows, theplate being located between the first plate 101 and the first plate 102.In the following description, parts common to Embodiment 4 andEmbodiment 1, 2, or 3 have the same reference signs, and detaileddescriptions thereof are omitted.

[Configuration of Refrigerant Distributer 2]

The configuration of the refrigerant distributer 2 according toEmbodiment 4 will be described. FIG. 12 is an exploded perspective viewillustrating an example of the configuration of a refrigerantdistributer according to Embodiment 4.

As illustrated in FIG. 12 , the refrigerant distributer 2 is formed bystacking a plurality of plates 40, which have, for example, arectangular shape. The plates 40 are formed by stacking the first plates101, 102, and 103, second plates 112, 113, and 114, and third plates 121and 122. The first plates 101, 102, and 103, the second plates 112, 113,and 114, and the third plates 121 and 122 have the same outside shape inplan view.

The refrigerant distributer 2 has the distribution passages 2 a, whichare formed by the passages of the first plates 101, 102, and 103, thesecond plates 112, 113, and 114, and the third plates 121 and 122. Thedistribution passages 2 a are formed by the first passage 10A, a fifthpassage 10E, a sixth passage 10F, seventh passages 10G, eighth passages10H, ninth passages 10I, tenth passages 10J, and eleventh passages 10K,the communication chambers 11, a first branch passage 12A, second branchpassages 12B, and third branch passages 12C, and first interlevel crosspassages 13A and second interlevel cross passages 13B.

The first plate 101 has the one or the plurality of first passages 10A,which are through holes and which are located at substantially thecenter of the first plate 101 in the short-side direction. FIG. 12illustrates an example in which a refrigerant pipe is connected to thefirst plate 101. In this case, the one first passage 10A is provided atsubstantially the center of the first plate 101.

The third plate 121 has the fifth passage 10E, which is a through holeand which is located at substantially the center of the third plate 121.The fifth passage 10E is formed at a position depending on the positionof the corresponding first passage 10A of the first plate 101 and allowsthe first passage 10A and the sixth passage 10F, which will be describedlater, to communicate with one another.

A pair of the seventh passages 10G, which are circular through holes andwhich are located at respective positions horizontal to the sixthpassage 10F, and a pair of the eighth passages 10H, which are circularthrough holes and which are located at respective positions symmetricalrelative to the sixth passage 10F in the height direction, are open inthe second plate 113. In addition, a pair of the ninth passages 10I,which are circular through holes and which are located at respectivepositions horizontal to each of the eighth passages 10H, and a pair ofthe tenth passages 10J, which are circular through holes and which arelocated at respective positions point-symmetrical relative to the eighthpassage 10H, are open in the second plate 113. The second plate 113 is athrough passage plate having the sixth passage 10F to the tenth passages10J, which serve as through passages.

The third plate 122 has the first branch passage 12A, which is astraight through groove extending in a horizontal direction, such thatthe first branch passage 12A communicates with the sixth passage 10F andthe seventh passages 10G of the second plate 113 in a state in which thethird plate 122 and the second plate 113 are stacked.

In addition, the third plate 122 has the second branch passages 12B,which are straight through grooves extending in the horizontaldirection, such that the second branch passages 12B are located atrespective positions symmetrical relative to the first branch passage12A in the height direction and each communicate with the correspondingeighth passage 10H and the corresponding ninth passages 10I.

Furthermore, the third plate 122 has the third branch passages 12C,which are through grooves. The third branch passages 12C are formed suchthat part of each of the third branch passages 12C extends straight inthe horizontal direction and such that respective end portions of thestraight part extend toward the opposite sides in the height direction.Both end portions of each of the third branch passages 12C are formed tobe connected to the corresponding eleventh passages 10K of the secondplate 114, which will be described later. The third plate 122 is abranch passage plate having the first branch passage 12A to the thirdbranch passages 12C, which serve as branch passages.

The third plate 121 has the first interlevel cross passages 13A, whichare a pair of through grooves extending in a height direction, such thatthe first interlevel cross passages 13A each communicate with thecorresponding seventh passage 10G and the corresponding eighth passage10H of the second plate 113 in a state in which the third plate 121 andthe second plate 113 are stacked. In addition, the third plate 121 hasthe second interlevel cross passages 13B, which are a pair of throughgrooves extending in the height direction, such that the secondinterlevel cross passages 13B each communicate with the correspondingninth passage 10I and the corresponding tenth passage 10J of the secondplate 113 in a state in which the third plate 121 and the second plate113 are stacked. The first interlevel cross passages 13A and the secondinterlevel cross passages 13B are each formed to cross the heat transfertubes 4 connected to the corresponding refrigerant outlet portions 2B,which are outlet ports, and to allow two passages to communicate withone another. The third plate 121 is an interlevel cross passage platehaving the first interlevel cross passages 13A and the second interlevelcross passages 13B, which serve as interlevel cross passages.

The second plate 114 has the eleventh passages 10K, which are throughholes. The eleventh passage 10K is formed at a position depending on theposition of an end portion of the corresponding third branch passage 12Cof the third plate 122 and allows the third branch passage 12C and thecorresponding communication chamber 11 of the first plate 102 tocommunicate with one another.

When the plates are stacked, the sixth passage 10F and the seventhpassages 10G are connected to the first branch passage 12A. In addition,the seventh passage 10G and the eighth passage 10H are connected torespective end portions of the corresponding first interlevel crosspassage 13A. The eighth passage 10H and the ninth passages 10I areconnected to the corresponding second branch passage 12B. The ninthpassage 10I and the tenth passage 10J are connected to respective endportions of the corresponding second interlevel cross passage 13B. Theeleventh passages 10K are connected to respective end portions of thecorresponding third branch passage 12C.

[Refrigerant Flow in Refrigerant Distributer 2]

Next, the refrigerant flow and the distribution passages 2 a in therefrigerant distributer 2 will be described with reference to FIG. 12 .When the heat exchanger 1 functions as an evaporator, two-phasegas-liquid refrigerant flows into the refrigerant distributer 2 from thefirst passage 10A of the first plate 101.

The refrigerant that has flowed into the refrigerant distributer 2 movesstraight in the fifth passage 10E of the third plate 121 and the sixthpassage 10F of the second plate 113, comes into contact with a surfaceof the second plate 114 in the first branch passage 12A of the thirdplate 122, and is diverted in the horizontal direction. The divertedrefrigerant flows move to respective end portions of the first branchpassage 12A and enter the pair of the respective seventh passages 10G.

The refrigerant flows that have entered the respective seventh passages10G move straight in the respective seventh passages 10G in thedirection opposite to the direction in which refrigerant moves in thefifth passage 10E and the sixth passage 10F. Each of the refrigerantflows enters one end of the corresponding first interlevel cross passage13A of the third plate 121, comes into contact with a surface of thefirst plate 101 in the first interlevel cross passage 13A, and movestoward the other end of the first interlevel cross passage 13A. Each ofthe refrigerant flows that has reached the other end of thecorresponding first interlevel cross passage 13A enters thecorresponding eighth passage 10H of the second plate 113.

The refrigerant flows that have entered the respective eighth passages10H move straight in the respective eighth passages 10H in the directionopposite to the direction in which refrigerant moves in the seventhpassage 10G. Each of the refrigerant flows comes into contact with thesurface of the second plate 114 in the corresponding second branchpassage 12B of the third plate 122 and is diverted in the horizontaldirection. The diverted refrigerant flows move to respective endportions of the corresponding second branch passage 12B and enter thepair of the respective ninth passages 10I.

The refrigerant flows that have entered the respective ninth passages10I move straight in the respective ninth passages 10I in the directionopposite to the direction in which refrigerant moves in the eighthpassage 10H. Each of the refrigerant flows enters one end of thecorresponding second interlevel cross passage 13B of the third plate121, comes into contact with the surface of the first plate 101 in thesecond interlevel cross passage 13B, and moves toward the other end ofthe second interlevel cross passage 13B. Each of the refrigerant flowsthat has reached the other end of the corresponding second interlevelcross passage 13B enters the corresponding tenth passage 10J.

The refrigerant flows that have entered the respective tenth passages10J move straight in the respective tenth passages 10J in the directionopposite to the direction in which refrigerant moves in the ninthpassage 10I. Each of the refrigerant flows comes into contact with thesurface of the second plate 114 in the corresponding third branchpassage 12C of the third plate 122 and is diverted in the horizontaldirection. The diverted refrigerant flows move to respective endportions of the corresponding third branch passage 12C and enter therespective eleventh passages 10K of the second plate 114. Then, therefrigerant flows move out from the respective eleventh passages 10K andenter the respective communication chambers 11 of the first plate 102.

Each of the refrigerant flows that has entered the correspondingcommunication chamber 11 enters the third passages 10C of the secondplate 112 that communicate with the communication chamber 11 and isdiverted. The diverted refrigerant flows enter the respective fourthpassages 10D of the first plate 103 and are equally distributed to theheat transfer tubes 4 connected to the respective fourth passages 10D.

In this example, the refrigerant distributer 2 in which refrigerantpasses through three kinds of branch passages, that is, along eightbranch paths has been described, but the configuration is not limitedthereto. The number of branch paths can be set to any number other thaneight by changing the number of branch passages.

As described above, in the refrigerant distributer 2 according toEmbodiment 4, the third plate 122 is disposed between the first plate101 and the first plate 102, the third plate 122 having the branchpassages through which refrigerant flowing in from the first passage 10Ais diverted into a plurality of refrigerant flows. This realizes themulti-branch refrigerant distributer 2 without increasing in size.Accordingly, it is possible to increase the total length of the heattransfer tubes 4 of the heat exchanger 1 and to thus improve the heatexchanger performance.

Embodiment 5

Next, Embodiment 5 will be described. The refrigerant distributer 2according to Embodiment 5 differs from that in Embodiment 4 in the shapeof the communication chamber 11 of the first plate 102. In the followingdescription, parts common to Embodiment 5 and Embodiment 1, 2, 3, or 4have the same reference signs, and detailed descriptions thereof areomitted.

[Configuration of Refrigerant Distributer 2]

The configuration of the refrigerant distributer 2 according toEmbodiment 5 will be described. FIG. 13 is an exploded perspective viewillustrating an example of the configuration of a refrigerantdistributer according to Embodiment 5.

As illustrated in FIG. 13 , the refrigerant distributer 2 is formed bystacking a plurality of plates 50, which have, for example, arectangular shape. The plates 50 are formed by stacking the first plates101, 102, and 103, the second plates 112, 113, and 114, and the thirdplates 121 and 122. The first plates 101 and 103, the second plates 112,113, and 114, and the third plates 121 and 122 are similar to those inEmbodiment 4.

The refrigerant distributer 2 has the distribution passages 2 a, whichare formed by the passages of the first plates 101, 102, and 103, thesecond plates 112, 113, and 114, and the third plates 121 and 122. Thedistribution passages 2 a are formed by the first passage 10A, the fifthpassage 10E, the sixth passage 10F, the seventh passages 10G, the eighthpassages 10H, the ninth passages 10I, the tenth passages 10J, and theeleventh passages 10K, the communication chambers 11, the first branchpassage 12A, the second branch passages 12B, and the third branchpassages 12C, and the first interlevel cross passages 13A and the secondinterlevel cross passages 13B.

The first plate 102 has the plurality of communication chambers 11, eachof which is formed to depend on the position of the corresponding secondpassage 10B of the second plate 111. In Embodiment 5, similarly toEmbodiment 3, the communication chamber 11 has the descent inhibitingportion 11 a.

In this manner, similarly to Embodiment 3, provision of the descentinhibiting portion 11 a in the communication chamber 11 causes the flowresistance in a lower part of the communication chamber 11 to be largerthan that in an upper part of the communication chamber 11. Accordingly,liquid refrigerant forming two-phase gas-liquid refrigerant is inhibitedfrom being unevenly distributed to flow in the lower part due togravity. As a result, the liquid refrigerant flows evenly in thecommunication chamber 11. Thus, it is possible to evenly distribute theliquid refrigerant to the heat transfer tubes 4 communicating with thecommunication chamber 11 when the liquid refrigerant flows out from thecommunication chamber 11 and to improve the performance of the heatexchanger 1.

In addition, the descent inhibiting portion 11 a is provided such thatthe descent inhibiting portion 11 a is unevenly located to be downstreamof the fluid flow. This causes two-phase gas-liquid refrigerant flowingin from the corresponding second passage 10B of the second plate 111 toflow in the part located upstream of the fluid flow more than in thepart located downstream of the fluid flow, thus improving the heattransfer performance of the part of the heat exchanger 1 locatedupstream of the fluid flow. Accordingly, it is possible to improve theheat exchanger performance.

As described above, in the refrigerant distributer 2 according toEmbodiment 5, the communication chamber 11 has the descent inhibitingportion 11 a, which is located lower than the top of the correspondingfirst passage 10A. This inhibits liquid refrigerant forming two-phasegas-liquid refrigerant flowing into the communication chamber 11 frombeing unevenly distributed to flow in the lower part due to gravity.Thus, the liquid refrigerant is distributed evenly to the heat transfertubes 4. Accordingly, it is possible to improve the heat exchangerperformance.

In the refrigerant distributer 2, the descent inhibiting portion 11 a isformed to be located downstream of the fluid flow. As a result, a largeramount of refrigerant flows in the part located upstream of the fluid,thus improving the heat transfer performance of the part locatedupstream thereof in which the amount of heat exchange is large.Accordingly, it is possible to improve the heat exchanger performance.

Embodiment 6

Next, Embodiment 6 will be described. The refrigerant distributer 2according to Embodiment 6 differs from that in Embodiment 5 in the shapeof branch passages of a third plate. In the following description, partscommon to Embodiment 6 and Embodiment 1, 2, 3, 4, or 5 have the samereference signs, and detailed descriptions thereof are omitted.

[Configuration of Refrigerant Distributer 2]

The configuration of the refrigerant distributer 2 according toEmbodiment 6 will be described. FIG. 14 is an exploded perspective viewillustrating an example of the configuration of a refrigerantdistributer according to Embodiment 6.

As illustrated in FIG. 14 , the refrigerant distributer 2 is formed bystacking a plurality of plates 60, which have, for example, arectangular shape. The plates 60 are formed by stacking the first plates101, 102, and 103, the second plates 112 and 113, and third plates 121and 123. The first plates 101, 102, and 103, the second plates 112 and113, and the third plates 121 and 123 have the same outside shape inplan view.

The refrigerant distributer 2 has the distribution passages 2 a, whichare formed by the passages of the first plates 101, 102, and 103, thesecond plates 112 and 113, and the third plates 121 and 123. Thedistribution passages 2 a are formed by the first passage 10A, the fifthpassage 10E, the sixth passage 10F, the seventh passages 10G, the eighthpassages 10H, the ninth passages 10I, and the tenth passages 10J, thecommunication chambers 11, the first branch passage 12A, the secondbranch passages 12B, and fourth branch passages 12D, and the firstinterlevel cross passages 13A and the second interlevel cross passages13B.

The first plate 101 has the one or the plurality of first passages 10A,which are through holes and which are located at substantially thecenter of the first plate 101 in the short-side direction. FIG. 14illustrates an example in which a refrigerant pipe is connected to thefirst plate 101. In this case, the one first passage 10A is provided atsubstantially the center of the first plate 101.

The third plate 121 has the fifth passage 10E, which is a through holeand which is located at substantially the center of the third plate 121.The fifth passage 10E is formed at a position depending on the positionof the corresponding first passage 10A of the first plate 101 and allowsthe first passage 10A and the sixth passage 10F, which will be describedlater, to communicate with one another.

The pair of the seventh passages 10G, which are circular through holesand which are located at respective positions horizontal to the sixthpassage 10F, and the pair of the eighth passages 10H, which are circularthrough holes and which are located at respective positions symmetricalrelative to the sixth passage 10F in the height direction, are open inthe second plate 113. In addition, the pair of the ninth passages 10I,which are circular through holes and which are located at respectivepositions horizontal to each of the eighth passages 10H, and the pair ofthe tenth passages 10J, which are circular through holes and which arelocated at respective positions point-symmetrical relative to the eighthpassage 10H, are open in the second plate 113. The second plate 113 is athrough passage plate having the sixth passage 10F to the tenth passages10J, which serve as through passages.

The third plate 123 has the first branch passage 12A, which is astraight through groove extending in a horizontal direction, such thatthe first branch passage 12A communicates with the sixth passage 10F andthe seventh passages 10G of the second plate 113 in a state in which thethird plate 123 and the second plate 113 are stacked. In addition, thethird plate 123 has the second branch passages 12B, which are straightthrough grooves extending in the horizontal direction, such that thesecond branch passages 12B are located at respective positionssymmetrical relative to the first branch passage 12A in the heightdirection and each communicate with the corresponding eighth passage 10Hand the corresponding ninth passages 10I.

Furthermore, the third plate 123 has the fourth branch passages 12D,which are through grooves. The fourth branch passages 12D are formedsuch that part of each of the fourth branch passages 12D extendsstraight in the horizontal direction and such that an upstream endportion of the straight part, the upstream end portion being one of endportions of the straight part located upstream of the fluid flow,extends upward and downward like a straight line. That is, the fourthbranch passage 12D is formed such that the upstream end portion extendsin two different directions parallel to the height direction. In otherwords, the fourth branch passage 12D has a shape in which a T shape isturned over sideways. The upstream end portion of the fourth branchpassage 12D is formed to be connected to the corresponding communicationchambers 11 of the first plate 102. The third plate 123 is a branchpassage plate having the first branch passage 12A, the second branchpassages 12B, and the fourth branch passages 12D, which serve as branchpassages.

The third plate 121 has the first interlevel cross passages 13A, whichare a pair of through grooves extending in a height direction, such thatthe first interlevel cross passages 13A each communicate with thecorresponding seventh passage 10G and the corresponding eighth passage10H of the second plate 113 in a state in which the third plate 121 andthe second plate 113 are stacked. In addition, the third plate 121 hasthe second interlevel cross passages 13B, which are a pair of throughgrooves extending in the height direction, such that the secondinterlevel cross passages 13B each communicate with the correspondingninth passage 10I and the corresponding tenth passage 10J of the secondplate 113 in a state in which the third plate 121 and the second plate113 are stacked. The first interlevel cross passages 13A and the secondinterlevel cross passages 13B are each formed to cross the heat transfertubes 4 connected to the corresponding refrigerant outlet portions 2B,which are outlet ports, and to allow two passages to communicate withone another. The third plate 121 is an interlevel cross passage platehaving the first interlevel cross passages 13A and the second interlevelcross passages 13B, which serve as interlevel cross passages.

When the plates are stacked, the sixth passage 10F and the seventhpassages 10G are connected to the first branch passage 12A. In addition,the seventh passage 10G and the eighth passage 10H are connected torespective end portions of the corresponding first interlevel crosspassage 13A. The eighth passage 10H and the ninth passages 10I areconnected to the corresponding second branch passage 12B. The ninthpassage 10I and the tenth passage 10J are connected to respective endportions of the corresponding second interlevel cross passage 13B.Different ones of the communication chambers 11 are connected torespective end portions of the corresponding fourth branch passage 12Dthat extend upward and downward like a straight line.

[Refrigerant Flow in Refrigerant Distributer 2]

Next, the refrigerant flow and the distribution passages 2 a in therefrigerant distributer 2 will be described with reference to FIG. 14 .When the heat exchanger 1 functions as an evaporator, two-phasegas-liquid refrigerant flows into the refrigerant distributer 2 from thefirst passage 10A of the first plate 101.

The refrigerant that has flowed into the refrigerant distributer 2 movesstraight in the fifth passage 10E of the third plate 121 and the sixthpassage 10F of the second plate 113, comes into contact with a surfaceof the first plate 102 in the first branch passage 12A of the thirdplate 123, and is diverted in the horizontal direction. The divertedrefrigerant flows move to respective end portions of the first branchpassage 12A and enter the pair of the respective seventh passages 10G.

The refrigerant flows that have entered the respective seventh passages10G move straight in the respective seventh passages 10G in thedirection opposite to the direction in which refrigerant moves in thefifth passage 10E and the sixth passage 10F. Each of the refrigerantflows enters one end of the corresponding first interlevel cross passage13A of the third plate 121, comes into contact with a surface of thefirst plate 101 in the first interlevel cross passage 13A, and movestoward the other end of the first interlevel cross passage 13A. Each ofthe refrigerant flows that has reached the other end of thecorresponding first interlevel cross passage 13A enters thecorresponding eighth passage 10H of the second plate 113.

The refrigerant flows that have entered the respective eighth passages10H move straight in the respective eighth passages 10H in the directionopposite to the direction in which refrigerant moves in the seventhpassage 10G. Each of the refrigerant flows comes into contact with thesurface of the first plate 102 in the corresponding second branchpassage 12B of the third plate 123 and is diverted in the horizontaldirection.

The diverted refrigerant flows move to respective end portions of thecorresponding second branch passage 12B and enter the pair of therespective ninth passages 10I.

The refrigerant flows that have entered the respective ninth passages10I move straight in the respective ninth passages 10I in the directionopposite to the direction in which refrigerant moves in the eighthpassage 10H. Each of the refrigerant flows enters one end of thecorresponding second interlevel cross passage 13B of the third plate121, comes into contact with the surface of the first plate 101 in thesecond interlevel cross passage 13B, and moves toward the other end ofthe second interlevel cross passage 13B. Each of the refrigerant flowsthat has reached the other end of the corresponding second interlevelcross passage 13B enters the corresponding tenth passage 10J.

The refrigerant flows that have entered the respective tenth passages10J move straight in the respective tenth passages 10J in the directionopposite to the direction in which refrigerant moves in the ninthpassage 10I. Each of the refrigerant flows comes into contact with thesurface of the first plate 102 in the corresponding fourth branchpassage 12D of the third plate 123 and moves to the corresponding endportion thereof located upstream of the fluid flow. Each of therefrigerant flows that has moved to the corresponding upstream endportion moves to respective end portions of the upstream end portion inan up-down direction and enters the corresponding communication chambers11 of the first plate 102.

Each of the refrigerant flows that has entered the correspondingcommunication chamber 11 enters the third passages 10C of the secondplate 112 that communicate with the communication chamber 11 and isdiverted. The diverted refrigerant flows enter the respective fourthpassages 10D of the first plate 103 and are equally distributed to theheat transfer tubes 4 connected to the respective fourth passages 10D.

As described above, in the refrigerant distributer 2 according toEmbodiment 6, the fourth branch passage 12D is formed such that theupstream end portion of the end portions of the straight part of thefourth branch passage 12D, the straight part extending in the horizontaldirection, the upstream end portion being located upstream of the fluidflow, extends in the two different directions parallel to the heightdirection.

As a result, a larger amount of refrigerant flows in the part locatedupstream of the fluid, thus improving the heat transfer performance ofthe part located upstream thereof in which the amount of heat exchangeis large. Accordingly, it is possible to improve the heat exchangerperformance.

Although Embodiments 1 to 6 have been described above, the presentdisclosure is not limited to Embodiments 1 to 6 described above. Variousmodifications and applications can be made without departing from thegist of the present disclosure. For example, in Embodiments 1 to 6, thebranch passages and the interlevel cross passages have each beendescribed as the entire passage being formed by a through groove passingthrough both sides of a plate, but the configuration is not limited tothis example. It is sufficient that the branch passages and theinterlevel cross passages partially communicate with the respectivepassages 10A to 10K. Thus, for example, the branch passages and theinterlevel cross passages may be shaped like a groove having a depthless than the thickness of a plate such that part of each of thepassages does not pass through a plate in the thickness direction.

1. A refrigerant distributer including a plurality of plates, therefrigerant distributer being configured to divert, into a plurality ofrefrigerant flows, refrigerant flowing in from one or a plurality ofinlet ports thereof and allow the refrigerant flows to be let out from aplurality of outlet ports thereof spaced from one another in a firstdirection, the plurality of plates comprising: an inflow plate havingone of the plurality of inlet ports; a communication plate having acuboid communication chamber communicating with the one of the pluralityof inlet ports of the inflow plate; and a heat transfer tube insertionplate into which a heat transfer tube communicating with one of theplurality of outlet ports is inserted, the heat transfer tube insertionplate having heat transfer tube insertion space through which aplurality of the heat transfer tubes communicate with the communicationchamber,. wherein the communication chamber has a descent inhibitingportion projecting from a side thereof in a second direction differentfrom the first direction and located lower than a top of the one or theplurality of inlet ports, the descent inhibiting portion beingconfigured to inhibit liquid refrigerant from descending, when therefrigerant in a two-phase gas-liquid state flows in from the one or theplurality of inlet ports.
 2. The refrigerant distributer of claim 1,wherein one or the plurality of inlet ports are formed in the inflowplate such that the one or the plurality of inlet ports are locatedupstream of a flow of the fluid, when a fluid flows in one directionoutside the heat transfer tube.
 3. The refrigerant distributer of claim1, wherein the plurality of plates further comprises a branch passageplate disposed between the inflow plate and the communication plate, thebranch passage plate having a branch passage through which therefrigerant flowing in from the one or the plurality of inlet ports isdiverted into a plurality of refrigerant flows in a second direction. 4.The refrigerant distributer of claim 3, wherein the branch passage isformed such that respective end portions of a straight part of thebranch passage, the straight part extending straight in the seconddirection, extend toward opposite sides in the first direction.
 5. Therefrigerant distributer of claim 3, wherein the branch passage is formedsuch that an upstream end portion of end portions of a straight part ofthe branch passage, the straight part extending straight in the seconddirection, the upstream end portion being located upstream of a flow ofthe fluid, extends in two different directions parallel to the firstdirection, when a fluid flows in one direction outside the heat transfertube.
 6. (canceled)
 7. The refrigerant distributer of claim 1, wherein,the descent inhibiting portion is unevenly located to be downstream of aflow of the fluid when a fluid flows in one direction outside the heattransfer tube.
 8. A heat exchanger comprising: the refrigerantdistributer of claim 1, and a plurality of heat transfer tubes connectedto the plurality of respective outlet ports.
 9. An air-conditioningapparatus comprising the heat exchanger of claim 8.